Bringing an asteroid back to Earth? What's that have to do with space exploration? If we were moving outward from there, and an asteroid is a good stopping point, then fine. But now it's turned into a whole planetary defense exercise at the cost of our outward exploration.
Space architectures capable of supporting a permanent human presence on Mars are extraordinarily complex, with many different interdependent systems.
What are you going to do with astronauts who first reach the surface of Mars and then turn around and rocket back home-ward? What are they going to do, write their memoirs? Would they go again? Having them repeat the voyage, in my view, is dim-witted. Why don't they stay there on Mars?
We need the next generation to be motivated and to push technological boundaries, to seek out new innovations.
The pilgrims on the Mayflower landed at Plymouth Rock. To my knowledge, they didn't wait around for a return trip to Europe. You settle some place with a purpose. If you don't want to do that, stay home. You avoid an awful lot of risks by not venturing outward.
NASA needs to focus on the things that are really important and that we do not know how to do. The agency is a pioneering force, and that is where its competitive advantage lies.
Some things just can't be described. And stepping onto the moon was one of them.
I am excited to think that the development of commercial capabilities to send humans into low Earth orbit will likely result in so many more Earthlings being able to experience the transformative power of space flight.
When you're in a spacecraft, you need to know what things you can touch and what things you shouldn't touch!
In space, you don't get that much noise. Noise doesn't propagate in a vacuum.
Before deciding what to do about national space policy, Obama set up an outside review panel of space experts, headed up by my friend Norm Augustine, former head of Lockheed Martin and a former government official.
Heavy lifting doesn't need to be heavy spending if we do the job right.
The biggest benefit of Apollo was the inspiration it gave to a growing generation to get into science and aerospace.
We can continue to try and clean up the gutters all over the world and spend all of our resources looking at just the dirty spots and trying to make them clean. Or we can lift our eyes up and look into the skies and move forward in an evolutionary way.
The way I see it, what is going to come out of the moon activities is a respect for U.S. leadership.
I don't think we're going to build a 50-person spacecraft or a 100-person spacecraft.
Space is not just going up and coming back down again. Space is getting into orbit and being there, living there, establishing a presence, a permanence.
I'm sure that there are places in the deserts in Australia that could be similar to where we might want to go on Mars.
I understand that Detroit was a pretty rough place to grow up in the '70s and '80s.
I think humans will reach Mars, and I would like to see it happen in my lifetime.
Mars is there, waiting to be reached.
Let's not spend resources that we don't need to be sending astronauts back to the moon. Let's not spend expensive resources on bringing people who have reached Mars back again. Prepare them to become a growing colony.
I think the people who experienced the Apollo missions came away from that experience wondering to themselves, 'When can we get a chance to experience spaceflight?' I've heard that many, many times: that people got into a new career field hoping that they would be able to experience spaceflight.
If we can conquer space, we can conquer childhood hunger.
Just as Mars - a desert planet - gives us insights into global climate change on Earth, the promise awaits for bringing back to life portions of the Red Planet through the application of Earth Science to its similar chemistry, possibly reawakening its life-bearing potential.
I am definitely not rich.
I want to keep on the move, keep stimulated and challenged.
As someone who flew two space capsules and twice landed in the ocean, I can attest from personal experience how much logistics work is needed to get you home.
By refocusing our space program on Mars for America's future, we can restore the sense of wonder and adventure in space exploration that we knew in the summer of 1969. We won the moon race; now it's time for us to live and work on Mars, first on its moons and then on its surface.
I want to reach a new generation. That's why I am Twittering now. I have a BlackBerry, an iPhone and a Mac.
The life expectancy of people going to Mars may be decreased by the higher level of radiation that they receive.
Armstrong described the lunar surface as 'beautiful.' I thought to myself, 'It's not really beautiful. It's magnificent that we're here, but what a desolate place we are visiting.'
Us reaching the moon convinced Gorbachev and other leaders that the Soviet Union couldn't compete with the U.S., so they revised their agenda. But people have short memories.
When the time comes to start building deep space transports and refueling rocket tankers, it will be the commercial industry that steps up, not another government-owned, government-managed enterprise.
I grew up in a country that I thought was special. And it was.
My father's an early aviator, and my first flight was with him at age two. Now, despite the fact that I got sick on the flight, I still enjoyed it, I believe.